From 06ef108cec98b3dfc0fba3f49e733a18eb9badd5 Mon Sep 17 00:00:00 2001 From: LE Manh Cuong Date: Sun, 7 Jul 2019 23:08:20 +0700 Subject: [PATCH] cmd/compile: fix unsafeValue handles OLSH/ORSH wrong For OLSH/ORSH, the right node is not a uintptr-typed. However, unsafeValue still be called recursively for it, causing the compiler crashes. To fixing, the right node only needs to be evaluated for side-effects, so just discard its value. Fixes #32959 Change-Id: I34d5aa0823a0545f6dad1ec34774235ecf11addc Reviewed-on: https://go-review.googlesource.com/c/go/+/185039 Run-TryBot: Cuong Manh Le TryBot-Result: Gobot Gobot Reviewed-by: David Chase Reviewed-by: Matthew Dempsky --- src/cmd/compile/internal/gc/escape.go | 7 ++++++- test/fixedbugs/issue32959.go | 17 +++++++++++++++++ 2 files changed, 23 insertions(+), 1 deletion(-) create mode 100644 test/fixedbugs/issue32959.go diff --git a/src/cmd/compile/internal/gc/escape.go b/src/cmd/compile/internal/gc/escape.go index 47ce853858..f92f4a7a6c 100644 --- a/src/cmd/compile/internal/gc/escape.go +++ b/src/cmd/compile/internal/gc/escape.go @@ -614,9 +614,14 @@ func (e *Escape) unsafeValue(k EscHole, n *Node) { } case OPLUS, ONEG, OBITNOT: e.unsafeValue(k, n.Left) - case OADD, OSUB, OOR, OXOR, OMUL, ODIV, OMOD, OLSH, ORSH, OAND, OANDNOT: + case OADD, OSUB, OOR, OXOR, OMUL, ODIV, OMOD, OAND, OANDNOT: e.unsafeValue(k, n.Left) e.unsafeValue(k, n.Right) + case OLSH, ORSH: + e.unsafeValue(k, n.Left) + // RHS need not be uintptr-typed (#32959) and can't meaningfully + // flow pointers anyway. + e.discard(n.Right) default: e.exprSkipInit(e.discardHole(), n) } diff --git a/test/fixedbugs/issue32959.go b/test/fixedbugs/issue32959.go new file mode 100644 index 0000000000..a0dc789a04 --- /dev/null +++ b/test/fixedbugs/issue32959.go @@ -0,0 +1,17 @@ +// compile + +// Copyright 2019 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Test escape analysis with shifting constant + +package main + +import "unsafe" + +func main() { + var l uint64 + var p unsafe.Pointer + _ = unsafe.Pointer(uintptr(p) + (uintptr(l) >> 1)) +} -- 2.50.0